The present invention relates to a sealing boot intended to ensure the sealing of a transmission joint connecting two shafts, of the type comprising a boot body having a bead at each end to contact and seal the periphery of the shaft or an element of the joint integral with the shaft.
The present invention relates to a sealing boot intended to ensure the sealing of a transmission joint connecting two shafts, of the type defined in the preamble of claim 1.
This type of sealing boot is frequently to be found disposed on two shafts which are connected for example by an articulation or a homokinetic joint such as a tripod joint. These boots are made from elastomer and have concentric or helical pleats and they confine lubricant in which the articulation or the joint is immersed.
The fixing of this type of boot is effected in a known manner by the clamping of fixing elements on each of the beads of the boot, thus clamping it firmly against each of the shafts or against a part integral with each shaft. These fixing elements can be closed rings, collars, particularly with a lug, or any other appropriate element. Apart from major deterioration of the membrane of the boot, the most critical zones in terms of good sealing of the device are located at the level of the clamped contacts between the interior of the beads and the corresponding shaft.
In the case where the fixing elements are swage-crimped closed rings there is a difficulty. In effect, the operation of crimping a fixing ring on the bearing surface of the bead necessitates fitting the ring and positioning it on the bead, then swaging it in order to bring it by plastic deformation into its mounted state. The swaging of the fixing ring is then made up of a first phase of deformation of this ring so as to bring its internal surface into simple contact with the bearing surface of the bead, then a second phase of deformation of the ring in order to make it penetrate into the bead by compressing the bearing surface. In contrast to the second phase, the first deformation phase does not in any way contribute to the clamping between the bead and the corresponding shaft. However, this first phase involves a first level of plastic deformation of the fixing ring, thus increasing the risks of it deteriorating and/or rupturing during the second phase of mounting, particularly if this mounting is automated, or during subsequent stresses in operation.